1. Field of the Invention
The present invention relates to a control apparatus and a control method for a variable valve mechanism that varies a valve characteristic of an engine valve (an intake valve or an exhaust valve) of an internal-combustion engine.
2. Description of Related Art
As this type of control apparatus, Japanese Laid-Open Patent Application Publication No. 2009-215955 discloses a technique for suppressing an overshoot in the operation of a variable valve mechanism due to an excessive portion of integration by stopping the calculation of an integral portion of a feedback manipulated variable when an operating speed is saturated, such as in a saturated state in which the manipulated variable of an actuator exceeds an outputtable actual manipulated variable.
However, the abovementioned technique is incapable of eliminating a difference between an actual operating position of the actuator and a desired angle caused by a difference between a feedforward manipulated variable and an actual manipulated variable when the actuator is in the saturated state. Thus, responsiveness is deteriorated with a resultant delay in convergence to a desired position.